AMD today launched the AMD Radeon HD 7970 graphics card
for desktop PCs, in what the company describes as the
world's fastest single GPU graphics card and the only
GPU based on 28nm production technology.

The Radeon HD 7970 is the first video card using a 28nm
GPU and to support Direct3D 11.1. And it's the first
video card implementing AMD's 28nm Graphics Core Next
architecture, which promises to enable new levels of
gaming and compute capabilities - realizing an
improvement of over 150% in performance/sq mm over the
prior generation.

Based on a complete AMD Tahiti GPU, the Radeon HD 7970
has 2048 stream processors organized according to AMD's
new SIMD-based GCN architecture. With a 384bit GDDR5
memory bus, the card has 4.31B transistors. Based on
TSMC's new 28nm High-K process, the GPU die size is
365mm2, making it a little bit smaller than AMD's 40nm
Cayman GPU at 389mm2.

The 7970 is clocked at 925MHz, giving it 3.79TFLOPs of
theoretical computing performance compared to 2.7TFLOPs
under the much different VLIW4 architecture of the
6970. Its 384bit GDDR5 memory bus for 7970 will be
clocked at 1.375GHz (5.5GHz data rate), giving it
264GB/sec of memory bandwidth, a boost over the
176GB/sec of the 6970.

AMD GPU
Specification Comparison

AMD Radeon HD 7970

AMD Radeon HD 6970

AMD Radeon HD 6870

AMD Radeon HD 5870

Stream
Processors

2048

1536

1120

1600

Texture
Units

128

96

56

80

ROPs

32

32

32

32

Core
Clock

925MHz

880MHz

900MHz

850MHz

Memory
Clock

1.375GHz (5.5GHz effective)
GDDR5

1.375GHz (5.5GHz effective)
GDDR5

1.05GHz (4.2GHz effective)
GDDR5

1.2GHz (4.8GHz effective)
GDDR5

Memory
Bus Width

384-bit

256-bit

256-bit

256-bit

Frame
Buffer

3GB

2GB

1GB

1GB

FP64

1/4

1/4

N/A

1/5

Transistor Count

4.31B

2.64B

1.7B

2.15B

Manufacturing Process

TSMC 28nm

TSMC 40nm

TSMC 40nm

TSMC 40nm

Price

$549

$350

$160

-

Other elements include 8 ROP partitions that can
process 32 ROPs per clock, 128 texture units divided up
among 32 Compute Units (CUs), and a fixed function
pipeline that contains a pair of AMD?s 9th generation
geometry engines.

Let's have a look at other features of AMD's first
Southern Island CPU.

The new card is also armed with the latest PCI Express
3.0 standard and is additionally equipped with GDDR5
memory.

Through its intelligent AMD PowerTune technology the
AMD Radeon HD 7970 converts unused power headroom into
extra performance by dynamically controlling clock
speeds, allowing gamers advanced performance inside of
the power envelope they specify. AMD's PowerTune
throttling technology will be coming to the entire
Southern Islands lineup. This means it remains
operationally the same by calculating the power draw of
the card based on load, and then altering clockspeeds
in order to keep the card below its PowerTune limit.
For the 7970 the limit is 250W, with the ability to
raise or lower it by 20% in the Catalyst Control
Center.

In addition, the AMD ZeroCore Power
technology found in the AMD Radeon HD 7970 ensures that
no power is wasted when the graphics card is not in
use, enabling lower idle power than any other currently
available graphics card.

Southern Islands for idle power consumption isn't
regular idle, rather it's "long idle, "as it is
described by AMD. Long idle is AMD's term for any
scenarios where the GPU can go completely idle.

For 7970 AMD has gotten regular idle power usage down
to 15W, 5W lower than it was on the 6900 series. AMD's
ZeroCore Power is the company's long idle power saving
technology. By implementing power islands on their GPUs
AMD can now outright shut off most of the functional
units of a GPU when the GPU is going unused. By doing
this AMD is able to reduce their power consumption from
15W at idle to under 3W in long idle. With support for
AMD CrossFire technology, AMD ZeroCore Power eliminates
wasted power, as well as additional heat and noise from
extra cards when you are not using them.

AMD Eyefinity 2.0 features all-new support for stereo
3D, universal bezel compensation, brand new display
configurations and an expanded field of view. This
allows users with 2560x1600 monitors in an AMD
Eyefinity 5x1 landscape configuration to achieve a
horizontal resolution of 12,800 pixels, driving more
than 20 million pixels of screen real estate.

AMD claims that the 7970 is going to be good
overclocker, with most cards to be able to hit 1GHz or
higher on the core clock and 6GHz or higher on the
memory clock with little effort even with the reference
cooler.

The card also fully supports 3GHz HDMI 1.4a and
DisplayPort 1.2 HBR2, ready to drive next generation
displays at up to 4K resolution.

The AMD Radeon HD 7970 is also backed by AMD's open 3D
initiative for stereo 3D gaming and Blu-ray 3D movies,
and fully supports DirectCompute and OpenCL
technologies.

Looking at the HD 7970 card, it is 10.5" going by the
PCB, but AMD has a metal reinforcement ring/plate
running along the entire card that sticks out the rear.
After accounting for this plate the total length of the
card is just 11", making the card roughly half an inch
longer than the 6970 and 5870.

AMD has also made some changes to the shrouding to
improve cooling. Compared to the 6970, 7970's blower is
a bit larger (~75mm) and the fins are slightly larger
to make use of that space. Meanwhile the heatsink is very similar to the 6970's.

The PCIe power sockets are the same 6+8pin
configuration as the 6970. Elsewhere at the front end
of the card we'll find the two CrossFire connectors,
supporting up to 3-way CrossFiree.

Back to the front of the card the is a single DL-DVI
port, along with an HDMI port and 2 miniDP ports all
along a single slot.

The AMD Radeon HD 7970 is available January 9, 2012
from retailers worldwide, with select models starting
at $549 US SEP.

According to the first reviews of the new card, the
7970 is around 15-25% faster than the GTX 580 but not
always, as its advantage is highly game dependent.
However, with the launch for AMD's Graphics Core Next
architecture, AMD has laid out a plan to seriously
break into the GPU computing market, taking on Nviddia'
Fermi architecture.